Multiple connections for electrical apparatus



May 7, 1946. E. s. McLARfi 2,399,753

MULTIPLE CONNECTIONS FOR ELECTRICAL APPARATUS Filed March 13, 1944 C 2 Sheets-Sheet 1 l 'n a :Fa

BY r ATTORNEY 4 E. s. MCLARN May 7, 1946.

MULTIPLE CONNECTIONS FOR ELECTRICAL APPARATUS 2 Sheets-Sheet 2 INVENTOR Zrzzes JM La/TIV Filed Marph 13, 1944 ATTORNEY Patented May 7, 1946 MULTIPLE CONNECTIONS FOR ELECTRICAL APPARATUS Ernest S. McLarn, Manhasset, N. Y., asslgnor to International Standard Electric Corporation, New York, N. Y., a corporation of Delaware Application March 13, 1944, Serial No. 526,286

13 Claims.

The present invention relates to multiple conductor straps for the making of multiple connections of electric apparatus such as the numerous strap or wire connections between the terminal studs or inserts as employed in the terminal blocks of telephone sets wherein bare conductor strapping is customarily employed. It further includes an improved method and circuit means to effect the welding of the connector straps to the terminal elements and to cause the severing or separation of the connector straps. As a result of the employment of the improved method of welding and for separation of the straps, very substantial economies obtain in the cost of manufacture and particularly as related to the assembling and welding operations.

In accordance with the present improvements in the making of the multiple electric connections between associated terminal inserts of a terminal block or like connected device, in place of employing the individual wire connection and soldering to the associated terminals there is employed an improved multiple connector unit. This unit is initially stamped out of flat metal to provide the required form of multiple connectors having their ends positioned to correspond to or to register with the positions of the terminal studs to be united and having greatly reduced section tie portions uniting the strap portions to provide an integral multiple connector unit The unit so formed and composed of the multiple connectors is placed over the terminals to be connected and in accordance with the present invention is welded to the terminal elements by P ssing a. welding current therethrough, the circuit of which is controlled by a suitable distributor to effect the welds successivel or in step by step manner. There is desirably employed a condenser discharge circuit whereby uniform welding results may be obtained.

After the spot welding of the strap portion to the terminals the tie portions of reduced section therebetween are severed or removed and this is very inexpensively and quickl performed by the passing of a heavier current therethrough in a manner to insure effective melting away of the tie portions as hereinafter described.

It is evident that melting of the strap ties could be done before the welding process and perhaps to some advantage since it would eliminate the small leakage current through the straps which occurs when welding is done first.

The foregoing and other features and advantages of the present improvements will be more fully understood by reference to the accompany.

ing drawings wherein like reference characters are applied to the corresponding portions in the several views.

Referring to the drawings:

Fig. 1 is a plan view of a flat metal multiple connector or multiple strap unit made in accordance with the invention;

Fig, 2 is a detailed sectional view illustrating the relative positioning of the parts in carrying out the welding and'severing operations.

Fig. 3 is a diagrammatic view illustrating the electrode block, the grounding block and the distributor and. circuit connections for effecting the welding and severing of the tie portions in accordance with the invention;

Fig. 4 is a diagrammatic plan view of the terminal block with a section of the multiple connector in place but with tie portions not removed;

Fig. 5 is a plan of the terminal block on com? pletion of the operation.

In accordance with the preferred embodiment of my invention there is formed a multiple strap or connector unit as illustrated in Fig. 1 composed of the connector or strap portions a which are united by the tie portions b of greatly reduced cross sectional area. The tie portions are of a section merely sufilcient for uniting and supporting the strap portions in their proper relation during handling and in the assembly operation. This multiple connector of skeleton pattern is desirably stamped out of sheet metal which may be of copper, bronze, silver, nickel or other metal v preferably non-corrosive and of approximately .005 inch gauge. As shown the ends of each of the strap portions are formed as circular enlargements positioned to correspond to or to register with the position of the terminal elements to which they are to be connected. The connector straps are of such form as is required for insulating and clearance relation to associated parts of for instance a terminal block of a telephone set carrying terminal inserts corresponding in position to the circular end portions of the connectors and to which these connectors are spot welded by the passing of a welding current through the circular end portions of the connectors while providing grounding connection to the terminal inserts.

In accordance with a desirable feature of the present invention a welding means and circuit arrangement is provided which permits of performing of the connection welding operation successively by positioning the terminal block with the multiple connector positioned on its terminals 56 and clamped between an electrode block'- and a dim enacting grounding block c provision permitting the welding operations to be performed in the one position and with the employment of the single set of electrodes.

In this preferred embodiment as illustrated the terminal block is shown having the customarily employed metal terminal elements at fitted to apertures therein and formed at their upper ends with the usual integral binding posts d to which the connecting straps are to be secured by welding. The multiple strap connector unit as explained is placed in proper position upon the terminal elements d and the welding is performed with the terminal block and multiple connector clampedloetween a removable or portable electrode block and a positioning and grounding block I, within which the terminal block is positioned. The electrode block is provided with a series of resiliently supported welding electrodes g, mounted on spring terminal supports it, as shown in Fig. 2. The errangement of these electrodes as will be readily understood, corresponds to the positioning of the terminal posts d and the end portions of the respective connecting straps of the multiple connector unit. In similar manner the grounding block is provided with resiliently supported grounding contacts i positioned to engage the end surface of each of the terminal inserts to efiect electrical connection therewith.

To perform the welding operation a welding current is passed from each electrode 9, through the connector units, terminal inserts and grounding contact i and while this may be performed by flash welding in which all welds would be made simultaneously it is preferred to accomplish this by means of the distributor controlled circuit arrangement as shown whereby the welds are for, it is required 3 reduced portions shall be removed and this can by cutting but in accordance with. a truth ture oi the invention is desirably effected o incorporation with the welding arrangenrnt described of a special circuit controlling means operative to melt or fuse away these tie portions in an effective and instantaneous operation. This the parts remaining in the welding position by the provision of circuit means operating to remove or eliminate grounding coneffected by current fed to each of the electrodes consecutively or in successive order and desirably from a condenser discharge source of supply. The circuit arrangement therefor as diagrammatically illustrated in Fig. 3, employs the distributor J having the usual rotating switch arm a engaging a series of stationary contacts each of which is connected by leads as shown to one of the electrodes of the electrode block. For the sake of clarity in following the circuits the distributor stationary contacts are indicated by the numerals i-I' to 5-5 as are likewise the electrodes to which they are connected; similar numeral indication being also applied to the related ends or the connector straps and to the correspondingly positioned terminal elements and grounding contacts to facilitate the tracing of the welding and severing circuits.

The distributor arm at its central point is indi eated as connected to a source of potential as a result or which, as it is progressed in the direction of the arrow, it will successively engage the contacts I to 5' thereby transmitting welding currentthrough the respective electrodes in a consecutive, step by step, manner during which period the circuit is closed to ground from the grounding contact 1 through the grounded leads k and k as diagrammatically shown in Fig. 3. The source of potential as desirably employed consists as shown ot a condenser discharge controlled circuit including the generator L having its one pole connected through rectifier l to the distributor switch arm and having the shunting condensers m and n, the latter having in series therewith a resistance 0.

Subsequent to the welding of the strap portions to the terminals, in the manner thus provided nections from certain of the grounding contacts which may be associated with alternately or intermediately positioned connecting straps whereby the potential applied to said connecting straps is constrained to pass through the tie portions and the terminals associated with an adjacent strap for completing the circuit to ground. The circuit provision therefor, as illustrated, includes a final position arrangement of stationary contacts 8, 9-9' and Ill-i0 oi thedistributor of which the contact 8 is connected intermediate of the condenser 12 and its series resistance. The distributor arm, as it moves into final position, first bridges the contacts 8 and 9' to complete a circuit over lead l2 'to ground including in series therewith the coil of relay i3. The relay i3 as shown has a movable contact I 4 normally closed on contact i5 connected to the grounding lead k associated with the grounding contacts of alternately positioned connector straps as indicated. As a resultthe energizing of the relay i3 removes the ground connections to the lead is and as related to this circuit arrangement the distributor arm finally bridges, first, the contacts 8 and In, the latter connected by means of lead I6 to the distributor contact 2 and, secondly, bridging 8 and I 0' of which the latter is connected by lead IE to contact '4. Thus the circuit as closed in the final positions will cause current to flow through intermediately positioned connector straps 2--2' and then through straps 4-4 to ground through the reduced section tie portions associated with the grounded contacts i, 3 and 5. By reason of the reduced section the tie portions will be melted away to sever the strap connections. In the circuit arrangement as illustrated and as a result of the connection l8 from contact 8 to the intermediate position as related to the condenser n the latter will at this time operate to impress, in conjunction with the discharge of the condenser m, an increased or heavy current flow through the circuit to insure melting away of the tie portions as will be readily understood. There is thus provided an improved welding means and circuit arrangement which with the employment of the special multiple connection unit permits of successfully welding a plurality of electric connections with substantial economy incident to the improved method wherein the tie portions are melted oil subsequent to the welding and without removal or alteration of the position of the electrode block. While there is described a preferred embodiment of the features of the invention it will be understood that varied modificatlon may be made therein without departing from the scope of the invention as defined in the claims, As illustrative thereof, while special provision is made for increasing the amplitude of the current for the final severing operation it will be understood that in the instance of connector units having very substantially reduced section tie portions the severing may-be accomplished without such increase in the volume of current.

Having described my invention, I claim: I

-1. The method of making multiple connections between terminals of electrical apparatus which consists initially in makinga multiple connector having connector strap portions and reduced section tie portions uniting strap portions to a plurality of laterally adjacent strap portions, placing the connector on the terminals, passing a weldin current through the connector and terminals only to effect welding of the strap portions, and

in situ separately melting away the tie portions by passing a current from a strap portion to an adjacent strap portion of an amplitude exceeding the conductive capacity of the tie portions.

2. The method of making multiple connections between terminals of electrical apparatus which consists initially in making an integral multipie connector unit having connector strap portions and reduced section tie portions uniting strap portions to a plurality of laterally adjacent strap portions, placing the connector unit on the terminals, and in situ passing a welding current through the connector and terminals to effect welding of the strap portions and finally melting away the tie portions by passing an increased amplitude current from a strap portion to'an adjacent strap portion.

3. An arrangement for making multiple connections between terminals of electrical apparatus employing a multiple connector unit formed with connector straps and with reduced area tie portions uniting strap portions to a plurality of laterally adjacent strapportions and to be removed, consisting of an electrode block having electrodes positioned to register with the terminals, circuit means connected to the electrodes for closing a welding circuit successively therethrough to the terminals, a potential source for the circuit means, contact means normally grounding the terminals and means to alter the circuit means to connect the connector unit tie portions in series by the circuit with opening of adjacent strap grounds whereby the tie portions will be melted oil? by the passing of current therethrough.

4. An arrangement for making multiple cori-v nections between terminals of electrical apparatus employing a multiple connector unit formed with connector straps and with reduced area tie portions uniting connector straps to a plurality of laterally adjacent straps and to be removed, consisting of an electrode block having electrodes positioned to register with the terminals, circuit means connected to the electrodes for closing a welding circuit successively therethrough to the terminals, 9, potential source for the circuit means and means to alter the circuit means to connect connector straps in series whereby the tie portions therebetween will be melted off by the passing of current therethrough.

5. An arrangement for making multiple connections between terminals of electrical apparatus employing a multiple connector unit formed with connector straps and with reduced area tie portions uniting connector straps to a plurality of laterally adjacent straps and to be removed, consisting of an electrode block having electrodes positioned to register with the terminals, circuit means connected to the electrodes and operative successively for closing a welding circuit therethrough tothe terminals, a potential source for the circuit means and means to alter the circuit means after welding to connect pairs of straps in series to include the connector unit tie portions in the circuit whereby they will be melted of! by the passing or current therethrouzh.

6. An arrangement for making multiple connections between terminals or electrical apparatus employing a multiple connector unit formed with connector straps and with reduced area tie portions uniting connector straps to a plurality of laterally adjacent straps and to be removed, consisting of an electrode block having electrodes p0- sitioned to register with the terminals, circuit means connected to the electrodes for successively closing a welding circuit therethrough to the terminals, a potential source for the circuit means and means to alter the circuit means after welding to connect pairs of straps in series to include the connector unit tie portions in the circuit whereby they will be melted of! by the passing of.

current therethrough and means for increasing the amplitude of the current when the circuit is so altered.

7. An arrangement for making multiple con nections between terminals of electrical apparatus employing a multiple connector unit formed with connector straps and with reduced area tie portions uniting connector straps to a plurality of laterally adjacent straps and to be removed, consisting of an electrode block having electrodes positioned to register with the terminals, circuit means including a distributor connected to the electrodes for closing a'welding circuit therethrough to the terminals in a consecutive manner, a potential source for the circuit means and means to alter the circuit means after welding to connect the connector unit tie portions inthe circuit whereby they will be melted off by the passing of current therethrough.

8. An arrangement .for making multiple connections between 'terminals or electrical apparatus employing a multiple connector unit formed with connector straps and with reduced area tie portions uniting connector straps to a plurality of laterally adjacent straps and to be removed, consisting of an electrode block having electrodes positioned to register with the terminals, circuit means including a distributor connected to the electrodes for closing a welding circuit therethrough to the terminals in a consecutive manner, a potential source for the circuit means and means to alter thecircuit means after welding to connect pairs of the straps in series relation to connect the connector unittie portions in the circuit whereby they will be melted off by the passing of current therethrough.

9. The arrangement as claimed in claim 8 hav- I trodes ositioned to register with the terminals, a,

grounding block having contacts to be engaged by the terminals, circuit means connected to the electrodes and grounding contacts including a distributor connected for closing of a welding circuit through the respective electrodes in a successive manner, a, potential source connected to the distributor and means to alter the circuit to cause the current to flow through the tie portions of the connector imit for the melting thereof.

11. Apparatus for making multiple connections to terminals or electrical apparatus employing a multiple connector unit having a plurality of connector straps positioned for connecting pairs of terminals of the apparatus and having reduced area tie portions uniting connector straps to a plurality of laterally adjacent straps and, consisting of an electrode block having electrodes positioned to register with the terminals, 9. grounding block having contacts to be engaged by the terminals, circuit means connected to the electrodes and grounding contacts including a distributor connected for closing of a welding circuit through the respective electrodes in a successive manner, a potential source connected to the distributor and said distributor having final position contacts connected to alter the circuit to close on alternate straps and to energize a relay having a movable contact connected for normally closing the circuit to the grounding contacts of the other of said straps thereby to cause the current to flow through the tie portions of the connector unit for the melting thereof.

12. The arrangement for making multiple connections to terminals of electrical apparatus emand, consisting of an electrode ploying a multiple connector unit having a pinrality of connector straps positioned for connecting pairs of terminals or the apparatus and having reduced area vtie portions uniting connector straps to a plurality of laterally adjacent strap:

block having electrodes positioned to register with the a grounding block having contacts to by the terminals, circuit means connected to the electrodes and grounding contacts including a distributor connected for closing of a welding circuit through the respective electrodes in a successive manner, a potential source connected to the distributor and said distributor having final position contacts connected to alter the circuit to connect pairs of straps in series to cause the current to flow through the tie portions of the connector unit for the melting removal thereof.

13. The arrangement as defined in claim 12 including a condenser discharge source of potential and connection therefrom to the final position distributor contact a capacity to increase the current amplitude under'the altered circuit condition.

ERNEST S. McLARN. 

